313 / | HD | ELECTRIC LAMP AND DISCHARGE DEVICES |
567 | DF | WITH GAS OR VAPOR {24} |
581 | DF | .~ Three or more electrode discharge device {9} |
595 | .~.~ Internal start or control electrode between discharge electrodes {3} | |
596 | DF | .~.~.~> Strip electrode |
597 | DF | .~.~.~> Interposed apertured electrode {2} |
600 | DF | .~.~.~> Two interposed electrodes |